"There are no guarantees, but if any of these therapies is targeting the right form of amyloid, and if this treatment is sufficiently safe and well tolerated, and if it’s started early enough, that could be a home run," Dr. Reiman said.
Starting early may be the key to maximizing benefit with disease-slowing therapies.
"By the time people have mild, but nondisabling memory impairment, their amyloid plaque load has reached its maximum. Tangles have already developed, and they’re beginning to lose synapses and neurons. We may need to start treatment years before onset of symptoms – and with newer imaging techniques we can see amyloid plaques 10-15 years before onset of symptoms" according to the psychiatrist.
He added that rigorous clinical trials are also warranted for some of the numerous unproven potential risk-reducing strategies known to be safe that have been identified in epidemiologic or neurobiologic studies in animals. These include statins, antihypertensive therapy, the Mediterranean diet, insulin-sensitizing agents, moderate consumption of alcohol, antioxidants, mental exercise and social activity, weight loss, and aerobic exercise.
"If you delay onset of Alzheimer’s disease by only 5 years without increasing life span, you have the potential to cut the number of new cases in half. That’s because Alzheimer’s dementia doubles in frequency every 5 years after age 60. And I think there are some treatments out there that maybe – no guarantee – have a more profound benefit than that," the psychiatrist said.
Dr. Reiman is a scientific adviser to Amnestix/Sygnis, AstraZeneca, Elan, Eli Lilly, GlaxoSmithKline, Seimens, Bayer, and Eisai. He receives research grant support from the National Institute on Aging, the Arizona Department of Health Services, AstraZeneca, Avid, and Kronos Life Sciences.